Bio-ingénierie du cartilage (original) (raw)
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Réparation du cartilage articulaire par matériaux biologiques
1996
The purpose of this study was to assess the joint cartilage's capacity for repair and the potential of various biological tissues as replacements for damaged cartilage. METHODS We operated 30.3 months old, lambs, creating a chondral lesion which was left untreated in group I and treated with a fresh chondral implant in group III, a frozen chondral implant in group IV, and a frozen periostal implant in group V ; in group II the lesion extended as far as the subchondral bone. The lesions were performed in the loading area of the medial condyle of the knee. Follow-up time was 6 months, and the results were assessed histologically. RESULTS In the chondral lesions which remained untreated (group I), degeneration of the exposed layers occurred, and loss of both cartilage thickness and homogeneity of the matrix was noted. Where the lesion extended as far as the subchondral bone (group II), repair was found to have taken place with a fibrous tissue indistinguishable from cartilage. When cartilage was implanted (groups III and IV), the integration of the implant depended on wether there was any contact between the implant and the surrounding tissue. DISCUSSION The integrity of the fresh implants was maintained better than that of the frozen ones, which were found to contain cells with a proliferative capacity. When periosteum was placed over the chondral lesion, we observed the formation of a very loose fibrous tissue in which the initial stages of differentiation could be appreciated in the deepest layers.
Etude structurelle en Microscopie Confocale Raman du cartilage produit par ingénierie tissulaire
2021
Articular cartilage is connective tissue, non-innervated and non-vascularized, that covers the ends of the bones within the joints. The high stresses to which the cartilage is subjected often lead to the alteration of the articular matrix. Defects in articular cartilage are generally associated with pain and loss of joint mobility, and have an impact on quality of life, including physical, social and economic well-being. Due to the lack of spontaneous regeneration or healing of cartilage, the use of tissue engineering techniques appears to be a promising avenue to address the clinical needs of patients with osteoarthritis and temporomandibular joint disorders (TMD). To optimize cartilage tissue engineering, non-invasive, non-destructive, high-resolution (nanometric) techniques are needed to evaluate the quality and structural arrangement of cartilage manufactured in vitro. The objective of our study was to follow the maturation of artificial cartilage under mechanical loads with inn...
La thérapie cellulaire du cartilage : bases cellulaires et moléculaires
Journal de la Société de Biologie, 2008
-L'augmentation de l'espérance de vie rend très urgente la mise au point de techniques de réparation des tissus lésés. Le cartilage articulaire est résistant,élastique et dure toute la vie. Il permet les mouvements des articulations et protége l'os sousjacent contre les agressions mécaniques et traumatiques. Mais lorsqu'il est lésé, le cartilage ne se répare pas spontanément. Aucun traitement médicamenteux n'étant efficaceà ce jour, il paraît licite d'agir précocement sur les lésions traumatiques du cartilage de façonà prévenir l'arthrose et reculer d'autant l'heure de la chirurgie prothétique. La thérapie cellulaire pourraitêtre une voie de prévention de la survenue de l'arthrose. Le cartilage ne contient qu'un seul type cellulaire, le chondrocyte qui synthétise et sécrète une abondante matrice protéique. Cette dernière assure le maintien des fonctions mécaniques du cartilage. Le concept de thérapie cellulaire consistè a combler la lésion cartilagineuse non seulement avec des chondrocytes sains, mais aussià reconstituer la structure et les propriétés physico-chimiques de la matrice. La greffe de chondrocytes autologues està la base de ce concept. Les recherches actuelles portent sur l'utilisation de cellules souches ou progénitrices, associéesà un biomatériau ((intelligent)) permettant le maintien du caractère chondrogénique des cellules, l'introduction du greffon dans la lésion articulaire par des méthodes peu invasives et l'acquisition de propriétés mécaniques proches de celle du cartilage natif. Mots clés : Cartilage / chondrocytes / biomatériaux / chitosan / cellules souches Abstract-Cell therapy in cartilage repair: cellular and molecular bases. The destruction of articular cartilage represents the outcome of most inflammatory and degenerative rheumatic diseases and leads to severe disability. Articular cartilage being unable to repair spontaneously, alterations of the joint surface often results in end-stage osteoarthritis, requiring surgical intervention and total joint replacement. This makes damaged tissues repair a major challenge in our aging society. Cartilage harbors only one cell type, the chondrocyte, which synthesizes and secretes specific matrix proteins such as type II collagen and high molecular weight proteoglycans. Matrix proteins are responsible for the conservation of the chondrocyte phenotype and the maintenance of the mechanical functions of cartilage. Development of therapeutic strategies for cartilage repair should thus comprise not only the replacement of lost cartilage cells but also that of extracellular matrix with cartilage-like properties. Different protocols are under investigation. The most commonly employed materials include transplantation of autologous osteochondral tissue. More recently, cell-based therapies using autologous mature chondrocytes or pre-chondrogenic stem cells have drawn particular attention. Tissue-engineering procedures represent the actual trend in cartilage repair. This approach combines biodegradable polymeric three-dimensional Article published by EDP Sciences 314 Société de Biologie de Paris matrixes and isolated prechondrogenic stem cells. The cells are seeded within the biocompatible matrix and then implanted into the joint. Numerous non-degradable and degradable polymers, which efficiently "mimic" the natural surroundings of cartilage cells, are currently under investigation.
RESUME L'étude histologique du cartilage nécessite une étape de décalcification après la fixation du tissu, dans le but d'obtenir des coupes de bonne qualité pour l'observation au microscope. La décalcification est une étape clef à prendre en considération dans les études de ce tissu. Il existe une multitude de décalcifiants, les plus couramment utilisés sont l'acide éthylène diamine tétracétique (EDTA) et les polyacides. Ils présentent tous des avanta-ges et des inconvénients comme par exemple un temps de décalcification trop long, la perte de l'intégrité du tissu, la destruc-tion d'épitopes… Depuis plusieurs années, de nouvelles formules commerciales sont disponibles, alliant parfois plusieurs types de décalcifiants. Notre étude propose de comparer les effets de 5 décalcifiants (EDTA et 4 décalcifiants commerciaux) sur le cartilage de genou et de disque intervertébral de souris âgées de 2 mois. Afin d'évaluer leur compatibi-lité avec les techniques d...
Ingénierie tissulaire autologue par distraction ostéogénique : considérations biomécaniques
Revue de Stomatologie et de Chirurgie Maxillo-faciale, 2011
Tissue engineering consists in producing functional replacement tissue. Distraction osteogenesis is a tissue engineering technique that uses the mechanical environment of cells to induce tissue regeneration, without need for exogenous biochemical factors. A better understanding of the optimal mechanical conditions of distraction callus stretching may reduce the duration, discomfort, and even social impact of distraction protocols, and complications and failures. We present the current state of knowledge in this field by addressing the fundamentals of elongating bone tissue biomechanics, the influence of rhythm and rate of distraction, and that of vectors and stability. Finally, we present the innovations currently studied, which may modify our clinical protocol in the short term.